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Offline sutefunu

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Coolant overflow
« on: August 22, 2019, 02:44:51 PM »
Hi guys,
Recently I started noticing the bike spraying coolant  from the overflow hose. Usually happens when it's above 30 C degrees and I'm riding on the highway at constant 180-200 kph for 20-30 minutes. The temperature gauge shows 4 bars while at high speed and in the city it goes to 5 bars then the fan kicks in and goes back to 4 bars. I notice the spraying by the marks by the left foot peg once I stop.
What could be the cause?

Offline Frontline

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Re: Coolant overflow
« Reply #1 on: August 22, 2019, 03:11:25 PM »
*Originally Posted by sutefunu [+]
Hi guys,
Recently I started noticing the bike spraying coolant  from the overflow hose. Usually happens when it's above 30 C degrees and I'm riding on the highway at constant 180-200 kph for 20-30 minutes. The temperature gauge shows 4 bars while at high speed and in the city it goes to 5 bars then the fan kicks in and goes back to 4 bars. I notice the spraying by the marks by the left foot peg once I stop.
What could be the cause?
Three can things can cause this: (they're a few others but given the info you've provided, not worth mentioning)
Over-filling the coolant
Radiator cap not holding pressure
Head-gasket leak (unlikely and other symptoms like dirty marks in overflow)

When engine is cold, verify the over-flow tank coolant level is between the H & L lines. If that is good, its likely the radiator cap needs replacing. The rad cap should hold 15.6psi to 19.9psi. When caps fail, they generally pop-off well below spec and allow fluid to be pushed back into the over-flow tank. The caps can be tested (with special tool) but they are not expensive and worth it to just replace and try.

Fix this ASAP because having it spray very slippery coolant in front of rear tire while traveling fast is asking for a major accident.
« Last Edit: August 22, 2019, 03:14:30 PM by Frontline »

Offline sutefunu

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Re: Coolant overflow
« Reply #2 on: August 22, 2019, 04:03:14 PM »
Thanks for the fast reply. I regularly check the coolant level and always try to keep it between H and L. I guess will have to find a way to measure the pressure.

Online Rick

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Re: Coolant overflow
« Reply #3 on: August 22, 2019, 05:39:05 PM »
Probably is the cap but before you go and replace it, check the sealing surface on both the cap and the rad, sometimes a crystalline deposit can build up that allows some leakage. Good luck.

Online zed9

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Re: Coolant overflow
« Reply #4 on: August 23, 2019, 02:43:37 AM »
I had my internal water pump seal leak and send some coolant out the weep hole in the water pump casting.
(This happened from the bike sitting idle over the winter. The leak stopped when the bike was ridden in the spring.)

You may want to check the weep hole. It's fairly common.

Online RobZ900

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Re: Coolant overflow
« Reply #5 on: August 23, 2019, 07:32:25 PM »
Sort of related, I checked my coolant overflow tank a few weeks back and it was approaching the low line. Stopped at Kawasaki and they didnt have or know what coolant was in the bike, only that it was green. They ended up giving me a bottle of coolant that was branded for Triumph. Colour of the coolant matched the stock stuff so not too fussed. Out of curiosity, how much do you find your bikes are using? Mine has taken a little over 2 years and 11,500 miles to go from full to low.
Motorcyclist - noun (moh-ter-sahy-klist)
: a person willing to take a container full of flammable liquid, place it on top of a hot, moving engine and then put the whole lot between their legs!

Offline OneOfTheNobodies

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Re: Coolant overflow
« Reply #6 on: August 31, 2019, 10:26:33 PM »
I pointed out that my overflow was a little under L at my 12000 km service and Kawasaki said that it did not matter since it was so little .. guess it is just me being paranoid .. about to get my 18000 km service and I am going to point it out again  :152: .. I have no problems with the bike overheating ...
Z900 2018 Black - Full Akrapovic system - Rear Seat Cowl - Rizoma Tomok Mirrors - Rizoma Breaklever RRC - Rizoma Clutchlever RRC - Rizoma Grips Sportline - Rizoma Bobbins 8x35 - Rizoma Footpegs - Rizoma Barend weights - Rizoma Oile Cap - Rizoma turnsignal - Rizoma Numberplate - Radiator Guard - SW Motech Kickstand Enlarger - SW Motech Crash Bars - SW Motech Micro Tankbag - Eazi Grip Tank Protector - Luimoto Seat Cover+Gold Gel - HealTech Break Light Pro

Online ras

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Re: Coolant overflow
« Reply #7 on: September 01, 2019, 02:50:55 AM »
Yup ...minor details👌